Data Access Manager

The Data Access Manager (DAM) was a database access system for the "classic" MacOS, introduced in 1991 as an extension to System 7. Similar in concept to ODBC, DAM saw little use and was eventually dropped in the late 1990s. Only a handful of products ever used it, although it was used for some extremely impressive demoware in the early 1990s.

Unlike ODBC, DAM left the actual query to whatever system was being used. That is, DAM had no SQL-like layers, which allowed for greater flexibility when talking to a variety of data sources. At the time this decision was almost impossible to avoid, as the power of the client machines was simply not enough to include a SQL translator in the DAM layer itself. Instead, DAM simply passed queries directly to underlying systems, which were expected to return results in a standardized format.

Like most Apple software, DAM attempted to make the process as easy as possible for the end user. One particularily notable addition in this respect was the concept of query documents, containing raw queries. This allowed the queries to be authored in external editors and simply "passed on" by client software, dramatically reducing the complexity of the client which only had to know how to open the document and receive result sets.

Although DAM was supposed to be agnostic about the data source, it was actually written as a way to easily interface Mac software with another Apple product, the Data Access Language, or DAL. DAL was a SQL-like language that was translated on the server-side into the underlying database's version of SQL (which at the time was completely unstandardized).